java web servlet编程题及答案，出10道题

1. 编写一个Servlet，将客户端提交的用户名和密码保存到数据库中。

public class LoginServlet extends HttpServlet {
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        String username = request.getParameter("username");
        String password = request.getParameter("password");

        // 将用户名和密码存储到数据库中

        response.getWriter().println("登录成功");
    }
}

2. 编写一个Servlet，查询数据库中的所有用户信息并返回给客户端。

public class UserServlet extends HttpServlet {
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // 查询数据库中的所有用户信息

        response.getWriter().println(users);
    }
}

3. 编写一个Servlet，接收客户端上传的文件并保存到服务器上。

public class UploadServlet extends HttpServlet {
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        Part filePart = request.getPart("file");
        String fileName = filePart.getSubmittedFileName();
        InputStream fileContent = filePart.getInputStream();

        // 将文件保存到服务器上

        response.getWriter().println("文件上传成功");
    }
}

4. 编写一个Servlet，从数据库中查询商品信息并返回给客户端。

public class ProductServlet extends HttpServlet {
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        int productId = Integer.parseInt(request.getParameter("productId"));

        // 查询数据库中的商品信息

        response.getWriter().println(product);
    }
}

5. 编写一个Servlet，从客户端接收订单信息并保存到数据库中。

public class OrderServlet extends HttpServlet {
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        String productName = request.getParameter("productName");
        int quantity = Integer.parseInt(request.getParameter("quantity"));
        double price = Double.parseDouble(request.getParameter("price"));

        // 将订单信息保存到数据库中

        response.getWriter().println("订单提交成功");
    }
}

6. 编写一个Servlet，查询数据库中的所有商品信息并返回给客户端。

public class ProductListServlet extends HttpServlet {
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // 查询数据库中的所有商品信息

        response.getWriter().println(products);
    }
}

7. 编写一个Servlet，从客户端接收用户名和密码并验证是否正确。

public class LoginServlet extends HttpServlet {
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        String username = request.getParameter("username");
        String password = request.getParameter("password");

        // 从数据库中查询用户信息并验证

        if (isValidUser) {
            response.getWriter().println("登录成功");
        } else {
            response.getWriter().println("用户名或密码错误");
        }
    }
}

8. 编写一个Servlet，从客户端接收用户ID并删除对应的用户信息。

public class DeleteUserServlet extends HttpServlet {
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        int userId = Integer.parseInt(request.getParameter("userId"));

        // 从数据库中删除用户信息

        response.getWriter().println("用户删除成功");
    }
}

9. 编写一个Servlet，从客户端接收商品ID并删除对应的商品信息。

public class DeleteProductServlet extends HttpServlet {
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        int productId = Integer.parseInt(request.getParameter("productId"));

        // 从数据库中删除商品信息

        response.getWriter().println("商品删除成功");
    }
}

10. 编写一个Servlet，从客户端接收用户ID和新密码并更新对应的用户密码。

public class ChangePasswordServlet extends HttpServlet {
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        int userId = Integer.parseInt(request.getParameter("userId"));
        String newPassword = request.getParameter("newPassword");

        // 更新用户密码

        response.getWriter().println("密码更新成功");
    }
}